Securing homes and businesses from unlawful intrusion and theft has been a major societal challenge for hundreds of years. The challenge continues today as security devices now represent a multi-billion dollar industry. The inventories of many booming security businesses include various sophisticated door and window locks. As with many efforts to defeat criminal activity, law-abiding citizens who attempt to secure their homes and businesses are forced to stay a step ahead of the latest technological tools of criminals.
Sophisticated and strong locks such as dead bolts on doors and windows are often considered a necessity for adequately protecting premises. As thieves become more clever at picking and defeating such locks, lock manufacturers are driven by consumer demand to produce ever better and more sophisticated locks. Further many insurance companies now routinely provide discounts or reductions to customers who elect to use the latest technologies for securing valuables.
Movies and police television programs frequently display the latest techniques used by criminals to break through locks and alarm systems. As an example, the advent of the low-cost and compact cordless drill has been shown numerous times in police dramas as an effective method for quickly defeating many otherwise strong locks. Such wide media exposure teaches the vulnerabilities of such locks to millions of people. Thus most criminals are now aware that a hardened steel drill bit directed down a lock cylinder and powered by a cordless drill can stealthily and quickly sheer off the pins of many conventional locks, rendering the lock easily opened.
Existing anti-drill features included on locks are often inadequate. For example anti-drill discs installed on the front face of some conventional lock cylinders are designed to spin when a drill bit is placed against the disc. However the discs often can be defeated by large high-speed bits that cause the discs to lock in place and then be drilled through.
Other anti-drill lock features are usable only on a single lock face, and are therefore not practical for implementation on dead-bolt locks that include two key access points, one on either side of a door or window.
Therefore there is a need for an improved lock cylinder, which can be applied to various types of locks, and which includes anti-drill features that are highly effective against drilling and that are also practical for use in dead bolt locks having key access from two sides.